The present invention relates to a method and apparatus to reduce false alerts by a collision warning system.
Forward Collision Warning (FCW) systems are available in the market today. FCW systems use information from the outside world through radar, laser based sensors, or cameras to detect if a target object is obstructing the path of the host vehicle and alert the driver if there is danger of a collision.
In addition to the FCW function, there are now more advanced features in the market that will go the additional step and apply some level of autonomous braking. These operations are called Automatic Emergency Braking (AEB) functions.
The objective of the forward collision warning function is to warn the driver if the time to collision is past a certain threshold. This functionality is dependent on the classification of objects in front of the vehicle in a field of view of a sensor.
At times, the radar signals may reflect from traffic signs or large metallic objects in the roadway on the ground with a signal strong enough to falsely classify the detected object as a target object.
If this occurs, a false positive warning will alert the driver when no vehicle is directly in front of the host vehicle. This false alert may be confusing or annoying to the driver, causing a loss of trust in the FCW system. In some cases, the function may even trigger an autonomous emergency braking that will reduce the speed of the vehicle. An escalation may put the driver in danger if it is a false event and other vehicles are tailgating behind. Eventually, the driver may be annoyed to a point of turning the FCW system off entirely or to ignore future warnings.